Field of the Invention
Embodiments of the invention relate to a quantum dot, and more particularly, to a quantum dot having high color purity and an eco-friendly property, and a quantum dot film, a light emitting diode (LED) package, and a display device including the same.
Discussion of the Related Art
Recently, as society has entered in earnest upon an information age, a field of display devices that represent all sorts of electrical signals as visual images has developed rapidly. For example, a flat panel display device, such as a liquid crystal display (LCD) device, a plasma display panel (PDP) device, a field emission display (FED) device, and an organic light emitting diode (OLED) device, has been introduced.
On the other hand, use of quantum dots (QD) to display devices has been researched or studied. In the QD, an electron in an unstable state transitions from a conduction band to a valence band such that light is emitted. Since the QD has a high extinction coefficient and excellent quantum yield, strong fluorescent light is emitted from the QD. In addition, since the wavelength of the light from the QD is controlled by a size of the QD, entire visible light can be emitted by controlling the size of the QD.
FIG. 1 is a schematic view illustrating the related art QD.
As shown in FIG. 1, the QD 1 includes a core 10 and a shell 20. Generally, cadmium selenide (CdSe) is widely used for the core 10. The QD 1 including the CdSe core 10 has an advantage in color purity.
However, cadmium (Cd) is harmful, and there is restriction in the use of the Cd.